The present invention relates to a golf club head, more particularly to a structure of the crown portion being capable of achieving a low center of gravity and a high restitution coefficient.
In the Japanese patent application publication Nos.2003-205055 and 2003-250935, as shown in FIG. 14 as “Ref.2”, a golf club head comprising a main body whose top is opened as illustrated in dotted line, and a crown plate made of a fiber reinforced resin closing the top opening, has been proposed. As the almost entirety of the crown portion of the head is made of the fiber reinforced resin, the kinetic energy which the head receives from a golf ball at impact is consumed in the fiber reinforced resin in the crown portion. In other words, it is difficult to decrease an energy loss at impact close to zero. As a result, there is a limit to the improvement in the rebound performance of such head. Further, as the vibrations of the crown portion are quickly damped, the reverberating time becomes short, and further, the frequency of the hitting sound becomes low in comparison with all metal head. Therefore, such a golf club head is not always good for many golfers in hit feeling.